Dr Holland replaced my aortic valve 10 years ago with a pig valve and it is still going strong no signs of needing replacement in fact I have since moved from SC to FL and my cardiologist asked me who did my surgery. He praised the job that Dr Holland did. I advised my cardiologist that when it needs to be replaced if time allows I will be driving back to SC or wherever Dr Holland is to have it replaced. I would highly recommend Dr Fred Holland he is a true professional, makes you feel very comfortable and lets you know what you can expect. I was not worried at all as I knew I was in good hands.